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++ VARYING vec2 texcoord;
++
++ void MAIN()
++
++ {
++ BASE_COLOR = texture(tex1, texcoord);
++ vec2 screencoord = texcoord;
++ // the tex coords from the rectangle (or cube etc.) are almost suitable,
++ // except that on non-GL we need to flip them
++ if (FRAMEBUFFER_Y_UP < 0.0)
++ screencoord.y = 1.0 - screencoord.y;
++ #if QSHADER_VIEW_COUNT >= 2
++ BASE_COLOR *= texture(SCREEN_TEXTURE, vec3(screencoord, VIEW_INDEX));
++ #else
++ BASE_COLOR *= texture(SCREEN_TEXTURE, screencoord);
++ #endif
++ }